I think WSJ#20 will go on sale as scheduled. Besides state of emergency doesn't equal to curfew or lockdown at all. We have already seen that with USA. Rather state of emergency is a preparatory step for a future lockdown, if needed.
That being said, even though it will lead to one less joy in my life, I would prefer Japan take precautionary lockdown to save lives.
In my country, we are going on what I would call is a soft curfew starting tonight. This should had been done two weeks ago (though the nature of my people means that enforcing lockdown is practically impossible).
If there should be lockdown in any country, it should be when the number of cases is still very low.